"Ghost Rule" is an original Japanese VOCALOID song featuring Hatsune Miku. It is one of the first songs written by DECO*27 after a brief hiatus in making music (at least in the VOCALOID field). The song was an instant hit on Niconico, having garnered over 100,000 views within the week of its publication. It has currently exceeded over 3 million views on niconico and 4 million views on YouTube. The song has entered the Hall of Legend.